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ly¡¡in¡¡size¡¡and¡¡shape£»¡¡but¡¡not¡¡at¡¡all¡¡in¡¡quality¡£¡¡But¡¡the¡¡Daltonian¡¡hypothesis¡¡conceived£»¡¡and¡¡nearly¡¡all¡¡the¡¡experimental¡¡efforts¡¡of¡¡the¡¡nineteenth¡¡century¡¡seemed¡¡to¡¡prove£»¡¡that¡¡there¡¡are¡¡numerous¡¡classes¡¡of¡¡atoms£»¡¡each¡¡differing¡¡in¡¡its¡¡very¡¡essence¡¡from¡¡the¡¡others¡£¡¡As¡¡the¡¡case¡¡stands¡¡to¡day¡¡the¡¡chemist¡¡deals¡¡with¡¡seventy¡odd¡¡substances£»¡¡which¡¡he¡¡calls¡¡elements¡£¡¡Each¡¡one¡¡of¡¡these¡¡substances¡¡is£»¡¡as¡¡he¡¡conceives¡¡it£»¡¡made¡¡up¡¡of¡¡elementary¡¡atoms¡¡having¡¡a¡¡unique¡¡personality£»¡¡each¡¡differing¡¡in¡¡quality¡¡from¡¡all¡¡the¡¡others¡£¡¡As¡¡far¡¡as¡¡experiment¡¡has¡¡thus¡¡far¡¡safely¡¡carried¡¡us£»¡¡the¡¡atom¡¡of¡¡gold¡¡is¡¡a¡¡primordial¡¡element¡¡which¡¡remains¡¡an¡¡atom¡¡of¡¡gold¡¡and¡¡nothing¡¡else£»¡¡no¡¡matter¡¡with¡¡what¡¡other¡¡atoms¡¡it¡¡is¡¡associated¡£¡¡So£»¡¡too£»¡¡of¡¡the¡¡atom¡¡of¡¡silver£»¡¡or¡¡zinc£»¡¡or¡¡sodiumin¡¡short£»¡¡of¡¡each¡¡and¡¡every¡¡one¡¡of¡¡the¡¡seventy¡odd¡¡elements¡£¡¡There¡¡are£»¡¡indeed£»¡¡as¡¡we¡¡shall¡¡see£»¡¡experiments¡¡that¡¡suggest¡¡the¡¡dissolution¡¡of¡¡the¡¡atomthat¡¡suggest£»¡¡in¡¡short£»¡¡that¡¡the¡¡Daltonian¡¡atom¡¡is¡¡misnamed£»¡¡being¡¡a¡¡structure¡¡that¡¡may£»¡¡under¡¡certain¡¡conditions£»¡¡be¡¡broken¡¡asunder¡£¡¡But¡¡these¡¡experiments¡¡have£»¡¡as¡¡yet£»¡¡the¡¡warrant¡¡rather¡¡of¡¡philosophy¡¡than¡¡of¡¡pure¡¡science£»¡¡and¡¡to¡day¡¡we¡¡demand¡¡that¡¡the¡¡philosophy¡¡of¡¡science¡¡shall¡¡be¡¡the¡¡handmaid¡¡of¡¡experiment¡£¡¡When¡¡experiment¡¡shall¡¡have¡¡demonstrated¡¡that¡¡the¡¡Daltonian¡¡atom¡¡is¡¡a¡¡compound£»¡¡and¡¡that¡¡in¡¡truth¡¡there¡¡is¡¡but¡¡a¡¡single¡¡true¡¡atom£»¡¡which£»¡¡combining¡¡with¡¡its¡¡fellows¡¡perhaps¡¡in¡¡varying¡¡numbers¡¡and¡¡in¡¡different¡¡special¡¡relations£»¡¡produces¡¡the¡¡Daltonian¡¡atoms£»¡¡then¡¡the¡¡philosophical¡¡theory¡¡of¡¡monism¡¡will¡¡have¡¡the¡¡experimental¡¡warrant¡¡which¡¡to¡day¡¡it¡¡lacks£»¡¡then¡¡we¡¡shall¡¡be¡¡a¡¡step¡¡nearer¡¡to¡¡the¡¡atom¡¡of¡¡Democritus¡¡in¡¡one¡¡direction£»¡¡a¡¡step¡¡farther¡¡away¡¡in¡¡the¡¡other¡£¡¡We¡¡shall¡¡be¡¡nearer£»¡¡in¡¡that¡¡the¡¡conception¡¡of¡¡Democritus¡¡was£»¡¡in¡¡a¡¡sense£»¡¡monistic£»¡¡farther¡¡away£»¡¡in¡¡that¡¡all¡¡the¡¡atoms¡¡of¡¡Democritus£»¡¡large¡¡and¡¡small¡¡alike£»¡¡were¡¡considered¡¡as¡¡permanently¡¡fixed¡¡in¡¡size¡£¡¡Democritus¡¡postulated¡¡all¡¡his¡¡atoms¡¡as¡¡of¡¡the¡¡same¡¡substance£»¡¡differing¡¡not¡¡at¡¡all¡¡in¡¡quality£»¡¡yet¡¡he¡¡was¡¡obliged¡¡to¡¡conceive¡¡that¡¡the¡¡varying¡¡size¡¡of¡¡the¡¡atoms¡¡gave¡¡to¡¡them¡¡varying¡¡functions¡¡which¡¡amounted¡¡to¡¡qualitative¡¡differences¡£¡¡He¡¡might¡¡claim¡¡for¡¡his¡¡largest¡¡atom¡¡the¡¡same¡¡quality¡¡of¡¡substance¡¡as¡¡for¡¡his¡¡smallest£»¡¡but¡¡so¡¡long¡¡as¡¡he¡¡conceived¡¡that¡¡the¡¡large¡¡atoms£»¡¡when¡¡adjusted¡¡together¡¡to¡¡form¡¡a¡¡tangible¡¡substance£»¡¡formed¡¡a¡¡substance¡¡different¡¡in¡¡quality¡¡from¡¡the¡¡substance¡¡which¡¡the¡¡small¡¡atoms¡¡would¡¡make¡¡up¡¡when¡¡similarly¡¡grouped£»¡¡this¡¡concession¡¡amounts¡¡to¡¡the¡¡predication¡¡of¡¡difference¡¡of¡¡quality¡¡between¡¡the¡¡atoms¡¡themselves¡£¡¡The¡¡entire¡¡question¡¡reduces¡¡itself¡¡virtually¡¡to¡¡a¡¡quibble¡¡over¡¡the¡¡word¡¡quality£»¡¡So¡¡long¡¡as¡¡one¡¡atom¡¡conceived¡¡to¡¡be¡¡primordial¡¡and¡¡indivisible¡¡is¡¡conceded¡¡to¡¡be¡¡of¡¡such¡¡a¡¡nature¡¡as¡¡necessarily¡¡to¡¡produce¡¡a¡¡different¡¡impression¡¡on¡¡our¡¡senses£»¡¡when¡¡grouped¡¡with¡¡its¡¡fellows£»¡¡from¡¡the¡¡impression¡¡produced¡¡by¡¡other¡¡atoms¡¡when¡¡similarly¡¡grouped£»¡¡such¡¡primordial¡¡atoms¡¡do¡¡differ¡¡among¡¡themselves¡¡in¡¡precisely¡¡the¡¡same¡¡way¡¡for¡¡all¡¡practical¡¡purposes¡¡as¡¡do¡¡the¡¡primordial¡¡elements¡¡of¡¡Anaxagoras¡£¡¡The¡¡monistic¡¡conception¡¡towards¡¡which¡¡twentieth¡¡¡century¡¡chemistry¡¡seems¡¡to¡¡be¡¡carrying¡¡us¡¡may¡¡perhaps¡¡show¡¡that¡¡all¡¡the¡¡so¡called¡¡atoms¡¡are¡¡compounded¡¡of¡¡a¡¡single¡¡element¡£¡¡All¡¡the¡¡true¡¡atoms¡¡making¡¡up¡¡that¡¡element¡¡may¡¡then¡¡properly¡¡be¡¡said¡¡to¡¡have¡¡the¡¡same¡¡quality£»¡¡but¡¡none¡¡the¡¡less¡¡will¡¡it¡¡remain¡¡true¡¡that¡¡the¡¡combinations¡¡of¡¡that¡¡element¡¡that¡¡go¡¡to¡¡make¡¡up¡¡the¡¡different¡¡Daltonian¡¡atoms¡¡differ¡¡from¡¡one¡¡another¡¡in¡¡quality¡¡in¡¡precisely¡¡the¡¡same¡¡sense¡¡in¡¡which¡¡such¡¡tangible¡¡substances¡¡as¡¡gold£»¡¡and¡¡oxygen£»¡¡and¡¡mercury£»¡¡and¡¡diamonds¡¡differ¡¡from¡¡one¡¡another¡£¡¡In¡¡the¡¡last¡¡analysis¡¡of¡¡the¡¡monistic¡¡philosophy£»¡¡there¡¡is¡¡but¡¡one¡¡substance¡¡and¡¡one¡¡quality¡¡in¡¡the¡¡universe¡£¡¡In¡¡the¡¡widest¡¡view¡¡of¡¡that¡¡philosophy£»¡¡gold¡¡and¡¡oxygen¡¡and¡¡mercury¡¡and¡¡diamonds¡¡are¡¡one¡¡substance£»¡¡and£»¡¡if¡¡you¡¡please£»¡¡one¡¡quality¡£¡¡But¡¡such¡¡refinements¡¡of¡¡analysis¡¡as¡¡this¡¡are¡¡for¡¡the¡¡transcendental¡¡philosopher£»¡¡and¡¡not¡¡for¡¡the¡¡scientist¡£¡¡Whatever¡¡the¡¡allurement¡¡of¡¡such¡¡reasoning£»¡¡we¡¡must¡¡for¡¡the¡¡purpose¡¡of¡¡science¡¡let¡¡words¡¡have¡¡a¡¡specific¡¡meaning£»¡¡nor¡¡must¡¡we¡¡let¡¡a¡¡mere¡¡word¡jugglery¡¡blind¡¡us¡¡to¡¡the¡¡evidence¡¡of¡¡facts¡£¡¡That¡¡was¡¡the¡¡rock¡¡on¡¡which¡¡Greek¡¡science¡¡foundered£»¡¡it¡¡is¡¡the¡¡rock¡¡which¡¡the¡¡modern¡¡helmsman¡¡sometimes¡¡finds¡¡it¡¡difficult¡¡to¡¡avoid¡£¡¡And¡¡if¡¡we¡¡mistake¡¡not£»¡¡this¡¡case¡¡of¡¡the¡¡atom¡¡of¡¡Democritus¡¡is¡¡precisely¡¡a¡¡case¡¡in¡¡point¡£¡¡Because¡¡Democritus¡¡said¡¡that¡¡his¡¡atoms¡¡did¡¡not¡¡differ¡¡in¡¡quality£»¡¡the¡¡modern¡¡philosopher¡¡has¡¡seen¡¡in¡¡his¡¡theory¡¡the¡¡essentials¡¡of¡¡monism£»¡¡has¡¡discovered¡¡in¡¡it¡¡not¡¡merely¡¡a¡¡forecast¡¡of¡¡the¡¡chemistry¡¡of¡¡the¡¡nineteenth¡¡century£»¡¡but¡¡a¡¡forecast¡¡of¡¡the¡¡hypothetical¡¡chemistry¡¡of¡¡the¡¡future¡£¡¡And£»¡¡on¡¡the¡¡other¡¡hand£»¡¡because¡¡Anaxagoras¡¡predicted¡¡a¡¡different¡¡quality¡¡for¡¡his¡¡primordial¡¡elements£»¡¡the¡¡philosopher¡¡of¡¡our¡¡day¡¡has¡¡discredited¡¡the¡¡primordial¡¡element¡¡of¡¡Anaxagoras¡£¡¡Yet¡¡if¡¡our¡¡analysis¡¡does¡¡not¡¡lead¡¡us¡¡astray£»¡¡the¡¡theory¡¡of¡¡Democritus¡¡was¡¡not¡¡truly¡¡monistic£»¡¡his¡¡indestructible¡¡atoms£»¡¡differing¡¡from¡¡one¡¡another¡¡in¡¡size¡¡and¡¡shape£»¡¡utterly¡¡incapable¡¡of¡¡being¡¡changed¡¡from¡¡the¡¡form¡¡which¡¡they¡¡had¡¡maintained¡¡from¡¡the¡¡beginning£»¡¡were¡¡in¡¡reality¡¡as¡¡truly¡¡and¡¡primordially¡¡different¡¡as¡¡are¡¡the¡¡primordial¡¡elements¡¡of¡¡Anaxagoras¡£¡¡In¡¡other¡¡words£»¡¡the¡¡atom¡¡of¡¡Democritus¡¡is¡¡nothing¡¡less¡¡than¡¡the¡¡primordial¡¡seed¡¡of¡¡Anaxagoras£»¡¡a¡¡little¡¡more¡¡tangibly¡¡visualized¡¡and¡¡given¡¡a¡¡distinctive¡¡name¡£¡¡Anaxagoras¡¡explicitly¡¡conceived¡¡his¡¡elements¡¡as¡¡invisibly¡¡small£»¡¡as¡¡infinite¡¡in¡¡number£»¡¡and¡¡as¡¡made¡¡up¡¡of¡¡an¡¡indefinite¡¡number¡¡of¡¡kindsone¡¡for¡¡each¡¡distinctive¡¡substance¡¡in¡¡the¡¡world¡£¡¡But¡¡precisely¡¡the¡¡same¡¡postulates¡¡are¡¡made¡¡of¡¡the¡¡atom¡¡of¡¡Democritus¡£¡¡These¡¡also¡¡are¡¡invisibly¡¡small£»¡¡these¡¡also¡¡are¡¡infinite¡¡in¡¡number£»¡¡these¡¡also¡¡are¡¡made¡¡up¡¡of¡¡an¡¡indefinite¡¡number¡¡of¡¡kinds£»¡¡corresponding¡¡with¡¡the¡¡observed¡¡difference¡¡of¡¡substances¡¡in¡¡the¡¡world¡£¡¡¡¨Primitive¡¡seeds£»¡¨¡¡or¡¡¡¨atoms£»¡¨¡¡were¡¡alike¡¡conceived¡¡to¡¡be¡¡primordial£»¡¡un¡¡¡changeable£»¡¡and¡¡indestructible¡£¡¡Wherein¡¡then¡¡lies¡¡the¡¡difference£¿¡¡We¡¡answer£»¡¡chiefly¡¡in¡¡a¡¡name£»¡¡almost¡¡solely¡¡in¡¡the¡¡fact¡¡that¡¡Anaxagoras¡¡did¡¡not¡¡attempt¡¡to¡¡postulate¡¡the¡¡physical¡¡properties¡¡of¡¡the¡¡elements¡¡beyond¡¡stating¡¡that¡¡each¡¡has¡¡a¡¡distinctive¡¡personality£»¡¡while¡¡Democritus¡¡did¡¡attempt¡¡to¡¡postulate¡¡these¡¡properties¡£¡¡He£»¡¡too£»¡¡admitted¡¡that¡¡each¡¡kind¡¡of¡¡element¡¡has¡¡its¡¡distinctive¡¡personality£»¡¡and¡¡he¡¡attempted¡¡to¡¡visualize¡¡and¡¡describe¡¡the¡¡characteristics¡¡of¡¡the¡¡personality¡£¡¡Thus¡¡while¡¡Anaxagoras¡¡tells¡¡us¡¡nothing¡¡of¡¡his¡¡elements¡¡except¡¡that¡¡they¡¡differ¡¡from¡¡one¡¡another£»¡¡Democritus¡¡postulates¡¡a¡¡difference¡¡in¡¡size£»¡¡imagines¡¡some¡¡elements¡¡as¡¡heavier¡¡and¡¡some¡¡as¡¡lighter£»¡¡and¡¡conceives¡¡even¡¡that¡¡the¡¡elements¡¡may¡¡be¡¡provided¡¡with¡¡projecting¡¡hooks£»¡¡with¡¡the¡¡aid¡¡of¡¡which¡¡they¡¡link¡¡themselves¡¡one¡¡with¡¡another¡£¡¡No¡¡one¡¡to¡day¡¡takes¡¡these¡¡crude¡¡visualizings¡¡seriously¡¡as¡¡to¡¡their¡¡details¡£¡¡The¡¡sole¡¡element¡¡of¡¡truth¡¡which¡¡these¡¡dreamings¡¡contain£»¡¡as¡¡distinguishing¡¡them¡¡from¡¡the¡¡dreamings¡¡of¡¡Anaxagoras£»¡¡is¡¡in¡¡the¡¡conception¡¡that¡¡the¡¡various¡¡atoms¡¡differ¡¡in¡¡size¡¡and¡¡weight¡£¡¡Here£»¡¡indeed£»¡¡is¡¡a¡¡vague¡¡fore¡shadowing¡¡of¡¡that¡¡chemistry¡¡of¡¡form¡¡which¡¡began¡¡to¡¡come¡¡into¡¡prominence¡¡towards¡¡the¡¡close¡¡of¡¡the¡¡nineteenth¡¡century¡£¡¡To¡¡have¡¡forecast¡¡even¡¡dimly¡¡this¡¡newest¡¡phase¡¡of¡¡chemical¡¡knowledge£»¡¡across¡¡the¡¡abyss¡¡o